3

持久性.xml

    <properties>
        <property name='javax.persistence.jdbc.driver' value='org.postgresql.Driver' />
        <property name='javax.persistence.jdbc.url'
            value='jdbc:postgresql://192.168.19.66:5432/service1' />
        <property name='javax.persistence.jdbc.user' value='postgres' />
        <property name='javax.persistence.jdbc.password' value='root' />
        <property name='hibernate.dialect' value='org.hibernate.dialect.PostgreSQLDialect' />
        <property name='hibernate.connection.shutdown' value='true' />
        <property name='hibernate.hbm2ddl.auto' value='none' />
        <property name='hibernate.show_sql' value='false' />
        <property name='hibernate.format_sql' value='false' />
                    <!-- Connection Pooling -->
        <property name="hibernate.connection.provider_class"
            value="org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider" />
        <property name="hibernate.c3p0.max_size" value="100" />
        <property name="hibernate.c3p0.min_size" value="5" />
        <property name="hibernate.c3p0.acquire_increment" value="5" />
        <property name="hibernate.c3p0.idle_test_period" value="500" />
        <property name="hibernate.c3p0.max_statements" value="50" />
        <property name="hibernate.c3p0.timeout" value="10000" />
    </properties>

例外

[C3P0PooledConnectionPoolManager[identityToken->1hge4qw8wh4gndjoawud4|b81be4]-AdminTaskTimer] DEBUG com.mchange.v2.async.ThreadPoolAsynchronousRunner - com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@5d1aef -- Running DeadlockDetector[Exiting. No pending tasks.]
[C3P0PooledConnectionPoolManager[identityToken->1hge4qw8wh4gndjoawud4|b81be4]-AdminTaskTimer] DEBUG com.mchange.v2.resourcepool.BasicResourcePool - Continuing acquisition series. pending_acquires [5],  attempts_remaining: 20
[C3P0PooledConnectionPoolManager[identityToken->1hge4qw8wh4gndjoawud4|b81be4]-AdminTaskTimer] DEBUG com.mchange.v2.async.ThreadPoolAsynchronousRunner - com.mchange.v2.async.ThreadPoolAsynchronousRunner@b66600: Adding task to queue -- com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask@934847
[C3P0PooledConnectionPoolManager[identityToken->1hge4qw8wh4gndjoawud4|b81be4]-HelperThread-#0] DEBUG com.mchange.v2.resourcepool.BasicResourcePool - An exception occurred while acquiring a poolable resource. Will retry.
java.sql.SQLException: No suitable driver
    at java.sql.DriverManager.getDriver(DriverManager.java:264)
    at com.mchange.v2.c3p0.DriverManagerDataSource.driver(DriverManagerDataSource.java:240)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:146)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:195)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:184)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:200)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1086)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquireAndDecrementPendingAcquiresWithinLockOnSuccess(BasicResourcePool.java:1073)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:44)
    at com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:648)

获取异常java.sql.SQLException: No proper driver。

当我查看源代码时，它正在寻找属性“hibernate.connection.driver_class”。我已经在“javax.persistence.jdbc.driver”中提到了驱动程序类。

我认为我没有以正确的方式配置连接池。该应用程序正在使用休眠 4.1.11（无弹簧）、JPA2、Postgresql 9.1。没有hibernate.cfg.xml。

问题

  • 在 Hibernate/JPA 应用程序中配置连接池的方法是什么。
  • 我已经在 javax.persistence.jdbc.driver 中提供了？如果我提供该hibernate.connection.driver_class属性，连接池和 JPA 连接创建的连接是相同还是不同？

笔记

  • Postgresql 驱动程序位于类路径中。
  • 如果我删除之后的行<!-- Connection Pooling -->，它会运行。但是如果我在<!-- Connection Pooling -->连接池之后添加行，我会得到这个异常。
4

2 回答 2

0

回到过去，您必须使用Class.forName(org.postgresql.Driver.class)构造加载适当的驱动程序类。使用 JDBC 4.0 驱动程序不再需要 - 但您可以尝试一下。

或者，尝试使用 启动您的应用程序-Djdbc.drivers=org.postgresql.Driver，它实际上与Class.forName代码片段相同，但不需要您对驱动程序类进行硬编码。希望能帮助到你。

于 2013-08-06T14:57:09.087 回答
0

从答案

https://stackoverflow.com/a/10899364/112500

我能够解决问题。

在将此行附加到 c3p0-config.xml 之后

<property name="driverClass">org.postgresql.Driver</property>
于 2013-08-07T08:09:09.557 回答